package com.sihan.swvp.filter;

import java.util.HashMap;
import java.util.Map;
import java.util.regex.Pattern;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

import org.apache.commons.lang3.StringUtils;

public class XssHttpServletRequestWrapper extends HttpServletRequestWrapper {

	HttpServletRequest orgRequest = null;

	public XssHttpServletRequestWrapper(HttpServletRequest request) {
		super(request);
	}

	/**
	 * 覆盖getParameter方法，将参数名和参数值都做xss过滤。<br/>
	 * 如果需要获得原始的值，则通过super.getParameterValues(name)来获取<br/>
	 * getParameterNames,getParameterValues和getParameterMap也可能需要覆盖
	 */
	@Override
	public String getParameter(String name) {
		String value = super.getParameter(xssEncode(name));
		if (value != null) {
			value = xssEncode(value);
		}
		return value;
	}

	/**
	 * 覆盖getHeader方法，将参数名和参数值都做xss过滤。<br/>
	 * 如果需要获得原始的值，则通过super.getHeaders(name)来获取<br/>
	 * getHeaderNames 也可能需要覆盖
	 */
	@Override
	public String getHeader(String name) {
		String value = super.getHeader(xssEncode(name));
		if (value != null) {
			value = xssEncode(value);
		}
		return value;
	}

	@Override
	public Map<String, String[]> getParameterMap() {
		Map<String, String[]> paramMap = new HashMap<String, String[]>(super.getParameterMap());
		for (Map.Entry<String, String[]> entry : paramMap.entrySet()) {
			String [] values = entry.getValue();
			String [] after = new String[values.length];
			int index=0;
			for(String value:values){
				after [index++]  = xssEncode(value);
			}
			entry.setValue(after);
		}
		return paramMap;
	}
	
	@Override
    public String[] getParameterValues(String name) {
		Map<String, String[]> paramMap = new HashMap<String, String[]>(super.getParameterMap());
        String[] results = paramMap.get(name);
        if (results == null || results.length <= 0)
            return null;
        else {
            int length = results.length;
            for (int i = 0; i < length; i++) {
                results[i] = xssEncode(results[i]);
            }
            return results;
        }
     }

	/**
	 * 将容易引起xss漏洞的半角字符直接替换成全角字符
	 * @param s
	 * @return
	 */
	private static String xssEncode(String s) {
		if (s == null || "".equals(StringUtils.trim(s))) {
			return s;
		}
		StringBuilder sb = new StringBuilder(s.length() + 16);
		for (int i = 0; i < s.length(); i++) {
			char c = s.charAt(i);
			switch (c) {
			case '>':
				sb.append('＞');// 全角大于号
				break;
			case '<':
				sb.append('＜');// 全角小于号
				break;
			case '\'':
				sb.append('‘');// 全角单引号
				break;
			case '\"':
				sb.append('“');// 全角双引号
				break;
			case '&':
				sb.append('＆');// 全角
				break;
			case '\\':
				sb.append('＼');// 全角斜线
				break;
			case '#':
				sb.append('＃');// 全角井号
				break;
			default:
				sb.append(c);
				break;
			}
		}
		return sb.toString();
	}

	/**
	 * 获取最原始的request
	 * @return
	 */
	public HttpServletRequest getOrgRequest() {
		return orgRequest;
	}

	/**
	 * 获取最原始的request的静态方法
	 * 
	 * @return
	 */
	public static HttpServletRequest getOrgRequest(HttpServletRequest req) {
		if (req instanceof XssHttpServletRequestWrapper) {
			return ((XssHttpServletRequestWrapper) req).getOrgRequest();
		}

		return req;
	}
	
	 public static String stripXSSAndSql(String value) {  
	        if (value != null) {  
	            Pattern scriptPattern = Pattern.compile("<[\r\n| | ]*script[\r\n| | ]*>(.*?)</[\r\n| | ]*script[\r\n| | ]*>", Pattern.CASE_INSENSITIVE);  
	            value = scriptPattern.matcher(value).replaceAll("");  
	            scriptPattern = Pattern.compile("src[\r\n| | ]*=[\r\n| | ]*[\\\"|\\\'](.*?)[\\\"|\\\']", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);  
	            value = scriptPattern.matcher(value).replaceAll("");  
	            scriptPattern = Pattern.compile("</[\r\n| | ]*script[\r\n| | ]*>", Pattern.CASE_INSENSITIVE);  
	            value = scriptPattern.matcher(value).replaceAll("");  
	            scriptPattern = Pattern.compile("<[\r\n| | ]*script(.*?)>", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);  
	            value = scriptPattern.matcher(value).replaceAll("");  
	            scriptPattern = Pattern.compile("eval\\((.*?)\\)", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);  
	            value = scriptPattern.matcher(value).replaceAll("");  
	            scriptPattern = Pattern.compile("e-xpression\\((.*?)\\)", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);  
	            value = scriptPattern.matcher(value).replaceAll("");  
	            scriptPattern = Pattern.compile("javascript[\r\n| | ]*:[\r\n| | ]*", Pattern.CASE_INSENSITIVE);  
	            value = scriptPattern.matcher(value).replaceAll("");  
	            scriptPattern = Pattern.compile("vbscript[\r\n| | ]*:[\r\n| | ]*", Pattern.CASE_INSENSITIVE);  
	            value = scriptPattern.matcher(value).replaceAll("");  
	            scriptPattern = Pattern.compile("onload(.*?)=", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);  
	            value = scriptPattern.matcher(value).replaceAll("");  
	        }  
	        return value;  
	    }  

}
